pci: call hotplug callback even when not hotplug case for later use.

call hotplug callback even when not hotplug case for later use.
And move hotplug check into hotplug callback.
PCIE slot needs this for card presence detection.
Signed-off-by: NIsaku Yamahata <yamahata@valinux.co.jp>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

hw/acpi_piix4.c

@@ -611,6 +611,9 @@ static int piix4_device_hotplug(DeviceState *qdev, PCIDevice *dev, int state)
     PIIX4PMState *s = DO_UPCAST(PIIX4PMState, dev,
                                 DO_UPCAST(PCIDevice, qdev, qdev));
 
+    if (!dev->qdev.hotplugged)
+        return 0;
+
     s->pci0_status.up = 0;
     s->pci0_status.down = 0;
     if (state) {

hw/pci.c

@@ -1514,7 +1514,8 @@ static int pci_qdev_init(DeviceState *qdev, DeviceInfo *base)
         pci_dev->romfile = qemu_strdup(info->romfile);
     pci_add_option_rom(pci_dev);
 
-    if (qdev->hotplugged) {
+    if (bus->hotplug) {
+        /* lower layer must check qdev->hotplugged */
         rc = bus->hotplug(bus->hotplug_qdev, pci_dev, 1);
         if (rc != 0) {
             int r = pci_unregister_device(&pci_dev->qdev);